/Engine/Plugins/FX/Niagara/Source/NiagaraEditor/Public/Widgets/SItemSelector.h
An optional delegate to get an array of categories for the specified item. Each category in the returned array represents one level of nested categories. NOTE: The OnCompareCategoriesForEquality, and OnGenerateWidgetForCategory delegates must be bound if this delegate is bound.
WidgetArgsType & OnGetCategoriesForItem &40; const FOnGetCategoriesForItem & InDelegate &41;